Laser receiver and angle sensor mounted on an excavator

Abstract

An improved level indicating system is provided for use with excavating equipment based upon a family of laser light receivers. In a first embodiment, a laser receiver with a single “long” photocell is mounted directly on the dipperstick of an excavator in a position that is designed to intercept pulses of laser light being emitted by a rotating laser light transmitter, and an angle-sensing sensor is also mounted to the dipperstick. In a second embodiment, a laser receiver with two parallel “long” photocells is mounted directly on the dipperstick, in which the pair of photocells are of sufficient precision to determine the angle of the dipperstick. In a third embodiment, a laser receiver with two parallel photocells is mounted directly on the dipperstick on a “servo mast” that can be re-positioned along the length of the dipperstick. The movable photocells thus can be shorter in length than the “long” photocells used in the second embodiment. In a fourth embodiment, a laser receiver with two or more parallel photocells is mounted on an “electric mast” which can have its elevation changed. Rotation sensors are mounted to the pivot joints between the platform and boom, the boom and dipperstick, and the dipperstick and bucket, so as to provide a complete solution in detecting the digging level with respect to the laser plane of light.